1. Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, P. R. China
2. School of Chemical Engineering and Australian Centre for NanoMedicine, University of New South Wales, Sydney, New South Wales 2052, Australia
3. Department of Bioengineering, Northeastern University, Boston, Massachusetts 02115, United States